The following vaccines should be reviewed with a health care provider as far in advance of travel as possible to ensure the proper scheduling of recommended vaccines.

Primary Vaccine SeriesFor travelers older than 2 years of age the following immunizations normally given during childhood should be up-to-date:

Measles, Mumps and Rubella (MMR) vaccine - at least 1 dose given on or after 12 months of age.

Diphtheria, Tetanus and Acellular Pertussis (DTaP) vaccine - 4 or 5 doses until age 7; after age 7, 1 dose of adult tetanus and diphtheria (Td) vaccine every 10 years.

Polio vaccine - at least 3 doses; inactivated polio vaccine (IPV) is currently recommended for routine vaccination in the United States.

Haemophilus influenzae type b (Hib) vaccine - 3 or 4 doses, depending on the brand; not routinely recommended after 5 years of age.

Hepatitis B vaccine - 3 doses

Varicella vaccine (for persons who have never had chickenpox) - 1 dose between the ages of 12 months and 13 years; 2 doses if 13 years or older.

Children older than 2 years should be "on schedule" with each vaccine's primary-series schedule, while adults should have completed the primary series. The number of doses needed depends on the child's age. If you are unsure about your vaccine history, consult with your physician.

In addition, adult travelers may want to consider:

Influenza (flu) vaccine - recommended for adults 65 years or older and for other high-risk individuals.

Pneumococcal vaccine - recommended for adults 65 years or older and for other high-risk individuals.

Booster or additional doses

TETANUS AND DIPHTHERIAA booster dose of adult tetanus-diphtheria (Td) is recommended every 10 years.

POLIOFor persons who have received a complete series of polio vaccine (either IPV or OPV), an additional single dose of vaccine should be received by persons 18 years of age and older traveling to the developing countries of Africa (Southern, Central, East, West, and North), Asia (East and Southeast), the Middle East and the Indian subcontinent, and the majority of the New Independent States of the former Soviet Union. This additional dose of polio vaccine is necessary for travelers to risk areas only once in adulthood. Inactivated polio vaccine (IPV) is recommended for this dose.

MEASLESPersons born in or after 1957 should consider a second dose of measles vaccine before traveling abroad.

The following immunizations may be recommended:

Yellow fever vaccine is recommended if traveling to certain parts of Africa and South America.

Hepatitis B vaccine should be considered for those who will live six months or more in areas where there are high rates of hepatitis B (Southeast Asia, Africa [Southern, Central, East, West and North], the Middle East, the islands of the South and Western Pacific, and the Amazon region of South America), and who will have frequent close contact with the local population. Children who have not previously received hepatitis B vaccine should be vaccinated. In general, hepatitis A vaccine and/or immune globulin (IG) is recommended for travelers to all areas EXCEPT Japan, Australia, New Zealand, Northern and Western Europe and North America (excluding Mexico).

Typhoid vaccine is recommended for travelers spending time in areas where food and water precautions are recommended (including many parts of the world, especially developing countries).

Meningococcal vaccine is recommended for travelers to sub-Saharan Africa (see map) during the dry season, which is from December through June, and especially if close contact with locals is anticipated.

Japanese encephalitis or tick-borne encephalitis vaccines should be considered for long-term travelers to areas of risk.

The risk of cholera to U.S. travelers is so low that it is questionable whether cholera vaccine is of benefit.

All vaccines (except cholera and yellow fever vaccines) may be safely administered simultaneously without any decrease in effectiveness. Immune globulin (IG) may be simultaneously administered at different body locations with an inactivated vaccine such as DTaP, IPV, Hib, and hepatitis A and B vaccines. However, IG diminishes the effectiveness of live-virus MMR and varicella vaccines if IG is given simultaneously. IG does not interfere with either OPV or yellow fever vaccine when given simultaneously.

Pregnancy and immunizationsWomen who are pregnant or who are likely to become pregnant within three months should not receive MMR or B vaccines. Yellow fever or polio (OPV) vaccines should be given to pregnant women only if there is a substantial risk of exposure. If given during pregnancy, waiting until the second or third trimester minimizes theoretical concerns over possible birth defects.

Women in the second and third trimesters of pregnancy have been found to be at increased risk of complications from influenza. Because currently available influenza vaccine is an inactivated vaccine, many experts consider influenza vaccination safe during any stage of pregnancy. A study of influenza vaccination of more than 2,000 pregnant women demonstrated no adverse fetal affects associated with influenza vaccine. However, more data are needed. Some experts prefer to administer influenza vaccine during the second trimester to avoid a coincidental association with spontaneous abortion (miscarriage), which is common in the first trimester, and because exposures to vaccines have traditionally been avoided during this time.

No convincing evidence for risk to the unborn baby from inactivated viral or bacterial vaccines or toxoids administered to pregnant women has been documented. These vaccines include: hepatitis A, hepatitis B, rabies, injectable typhoid, meningococcal, pneumococcal, tetanus-diphtheria toxoid (adult formulation) and IPV. Immune globulin can be given to pregnant women. Specific information is not available on the safety of cholera vaccine during pregnancy; therefore, it is prudent on theoretical grounds to avoid vaccinating pregnant women.

All vaccines may be administered safely to children of pregnant women and to breast-feeding mothers.